diff options
| author | Baolin Wang <baolin.wang@linux.alibaba.com> | 2023-07-07 16:51:47 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-08-18 10:12:14 -0700 |
| commit | e6e0c7673012f42c6fb8d89af71cd7607c93e0a5 (patch) | |
| tree | 040d8d40c943fbb17f33ea00b4a2913407b4a92f /mm/compaction.c | |
| parent | 94ec20035b05f842dc08277a5a90fba757088f39 (diff) | |
mm: compaction: skip the memory hole rapidly when isolating free pages
Just like commit 9721fd82351d ("mm: compaction: skip memory hole
rapidly when isolating migratable pages"), I can see it will also take
more time to skip the larger memory hole (range: 0x1000000000 -
0x1800000000) when isolating free pages on my machine with below memory
layout. So like commit 9721fd82351d, adding a new helper to skip the
memory hole rapidly, which can reduce the time consumed from about 70us
to less than 1us.
[ 0.000000] Zone ranges:
[ 0.000000] DMA [mem 0x0000000040000000-0x00000000ffffffff]
[ 0.000000] DMA32 empty
[ 0.000000] Normal [mem 0x0000000100000000-0x0000001fa7ffffff]
[ 0.000000] Movable zone start for each node
[ 0.000000] Early memory node ranges
[ 0.000000] node 0: [mem 0x0000000040000000-0x0000000fffffffff]
[ 0.000000] node 0: [mem 0x0000001800000000-0x0000001fa3c7ffff]
[ 0.000000] node 0: [mem 0x0000001fa3c80000-0x0000001fa3ffffff]
[ 0.000000] node 0: [mem 0x0000001fa4000000-0x0000001fa402ffff]
[ 0.000000] node 0: [mem 0x0000001fa4030000-0x0000001fa40effff]
[ 0.000000] node 0: [mem 0x0000001fa40f0000-0x0000001fa73cffff]
[ 0.000000] node 0: [mem 0x0000001fa73d0000-0x0000001fa745ffff]
[ 0.000000] node 0: [mem 0x0000001fa7460000-0x0000001fa746ffff]
[ 0.000000] node 0: [mem 0x0000001fa7470000-0x0000001fa758ffff]
[ 0.000000] node 0: [mem 0x0000001fa7590000-0x0000001fa7ffffff]
[shikemeng@huaweicloud.com: avoid missing last page block in section after skip offline sections]
Link: https://lkml.kernel.org/r/20230804110454.2935878-1-shikemeng@huaweicloud.com
Link: https://lkml.kernel.org/r/20230804110454.2935878-2-shikemeng@huaweicloud.com
Link: https://lkml.kernel.org/r/d2ba7e41ee566309b594311207ffca736375fc16.1688715750.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/compaction.c')
| -rw-r--r-- | mm/compaction.c | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index 43358efdbdc2..02239abed6ce 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -249,11 +249,36 @@ static unsigned long skip_offline_sections(unsigned long start_pfn) return 0; } + +/* + * If the PFN falls into an offline section, return the end PFN of the + * next online section in reverse. If the PFN falls into an online section + * or if there is no next online section in reverse, return 0. + */ +static unsigned long skip_offline_sections_reverse(unsigned long start_pfn) +{ + unsigned long start_nr = pfn_to_section_nr(start_pfn); + + if (!start_nr || online_section_nr(start_nr)) + return 0; + + while (start_nr-- > 0) { + if (online_section_nr(start_nr)) + return section_nr_to_pfn(start_nr) + PAGES_PER_SECTION; + } + + return 0; +} #else static unsigned long skip_offline_sections(unsigned long start_pfn) { return 0; } + +static unsigned long skip_offline_sections_reverse(unsigned long start_pfn) +{ + return 0; +} #endif /* @@ -1668,8 +1693,15 @@ static void isolate_freepages(struct compact_control *cc) page = pageblock_pfn_to_page(block_start_pfn, block_end_pfn, zone); - if (!page) + if (!page) { + unsigned long next_pfn; + + next_pfn = skip_offline_sections_reverse(block_start_pfn); + if (next_pfn) + block_start_pfn = max(next_pfn, low_pfn); + continue; + } /* Check the block is suitable for migration */ if (!suitable_migration_target(cc, page)) |